New colonoscope technology: impact on image capture and quality and on confidence and accuracy of endoscopy-based polyp discrimination.

BACKGROUND AND STUDY AIMS: A newer colonoscope series has optical magnification and improvement in image freezing function. We aimed to assess the impact on image capture, image quality, and polyp discrimination. PATIENTS AND METHODS: In consecutive patients undergoing outpatient colonoscopy images of colorectal polyps were taken with Olympus 190 or 180 series instruments. The number of image captures needed to obtain an adequate image, quality of stored images, proportion of polyps with a high confidence estimate of likely histology, and accuracy of interpretations were compared. RESULTS: An acceptable image at the first attempt was obtained in 97.3 % of photos with the 190 device vs. 83.8 % with the 180 instrument (P < 0.001). In the 190 group narrowband imaging (NBI) provided high confidence readings in 9 % more cases than in the 180 group, but did not improve accuracy of polyp categorization. The quality of the stored images was judged better for the 190 device. However, when images that had provided high confidence estimates of polyp histology were re-interpreted later by the original endoscopist, there was agreement with the original interpretation for > 98 % of polyps in both the 180 group and the 190 group. A second endoscopist agreed with the original high confidence interpretations for 90 % of polyps imaged with either the 180 or the 190 scope. CONCLUSION: The new colonoscope had less image blurring, improved subjective quality of stored images, and increased the proportion of high confidence endoscopic estimates of polyp histology, but did not improve accuracy in estimating polyp histology.

Ammonia level at admission predicts in-hospital mortality for patients with alcoholic hepatitis.

OBJECTIVE: Alcoholic hepatitis (AH), a unique clinical syndrome among patients with chronic and active alcohol use, is associated with high short-term mortality. An elevated ammonia level is associated with mortality in patients with acute liver failure; however, its impact in AH has not been well-studied. METHODS: A retrospective study was performed on patients admitted to a tertiary-care hospital with the discharge diagnosis of AH. Patients meeting criteria for AH were included in the final data analysis. Multivariate logistic regression models were built to examine the impact of serum ammonia in predicting in-hospital mortality (IHM) and 30-day mortality (TDM). Subgroup analysis was also performed, which was limited to patients who had hepatic encephalopathy. RESULTS: Of the 105 AH patients included, 26 (25%) died during the initial hospitalization. Among the 79 patients who survived initial hospitalization, 30 (39%) died within 30 days. Information about ammonia levels at admission was available for 82 patients. Of these, 25 patients had IHM and significantly higher ammonia level (97 vs. 69 µmol/L, P < 0.01). Among the 57 who survived hospitalization, ammonia levels were not significantly different (71 vs. 67 µmol/L, P = 0.69) in patients with and without TDM. The addition of ammonia to the multivariate regression models including age, sex, cirrhosis, treatment and model for end-stage liver disease (MELD) score improved the C statistics for IHM from 0.708 to 0.801 and for TDM from 0.756 to 0.766, respectively. These results were identical, even when limited to patients with hepatic encephalopathy. CONCLUSION: AH patients with elevated ammonia levels at admission have higher IHM; however, they do not seem to play a significant role in 30-day mortality for patients who survived hospitalization.

Genetic and molecular characterization reveals a unique nucleobase cation symporter 1 in Arabidopsis.

Locus At5g03555 encodes a nucleobase cation symporter 1 (AtNCS1) in the Arabidopsis genome. Arabidopsis insertion mutants, AtNcs1-1 and AtNcs1-3, were used for in planta toxic nucleobase analog growth studies and radio-labeled nucleobase uptake assays to characterize solute transport specificities. These results correlate with similar growth and uptake studies of AtNCS1 expressed in Saccharomyces cerevisiae. Both in planta and heterologous expression studies in yeast revealed a unique solute transport profile for AtNCS1 in moving adenine, guanine and uracil. This is in stark contrast to the canonical transport profiles determined for the well-characterized S. cerevisiae NCS1 proteins FUR4 (uracil transport) or FCY2 (adenine, guanine, and cytosine transport).